The journalist and black nationalist leader Marcus Garvey wrote a poem about it. The reggae great Bob Marley sang about it. And the Libyan strongman Moammar Gadhafi poured his oil wealth into it. But none lived to see a United States of Africa.

This history of disappointed hopes will provide the backdrop in early August when President Barack Obama hosts the inaugural U.S.-Africa summit in Washington. Only a few of Africa's 54 leaders—including Zimbabwe's President Robert Mugabe, who is still the target of U.S. sanctions—haven't been invited.

The U.S. wants to discuss continent-wide issues, such as security and terrorism, and to promote regional initiatives, such as shared electricity. To stress the breadth of the meeting's aims, Mr. Obama plans to meet with the African heads of state as a group, not individually—a move that has ruffled some diplomatic feathers.

From Marcus Garvey to Bob Marley, see leading figures who championed a United States of Africa.

The vision of an impoverished continent of countries coming together as one, flexing its muscle in geopolitics and the global economy, has long enticed activists, poets and politicians. But today's Africa remains divided, largely along hastily drawn colonial-era borders. The question now is whether the still-remote idea of political unity can find new life in the more modest goal of an integrated economic community.

The obstacles are formidable. Congolese women who trade eggs can't cross borders without giving away part of their load to officials and facing threats of sexual assault, according to a 2012 World Bank report; South Africa has feuded with Nigeria and Kenya over visa rules for their citizens; and a territorial row between Malawi and Tanzania over a lake separating them has hampered oil exploration.

Some Africa experts warn that the Obama administration's effort to deal with the continent as a whole may be counterproductive, both diplomatically and strategically. "It's uniquely American. It's different. It's also high-risk," says Stephen Hayes, president of the Corporate Council on Africa, a Washington, D.C., trade organization.

The U.S. plays down such concerns. Mr. Obama will set aside "lots of time for the leaders during the summit," Assistant Secretary of State for African Affairs Linda Thomas-Greenfield said earlier this month, adding that protocol and security would be handled in a way that shows "respect for African leaders."

The more substantive question is whether this is the best approach for promoting U.S. interests on the continent. Several U.S. competitors have focused more on the immediate needs of individual African states than on the long-term possibilities of a united continent.

China, which devotes half of its $14.41 billion aid budget to the continent, regularly hosts individual African heads of state. At an Africa summit hosted by Japan in Tokyo in June, Prime Minister Shinzo Abe held 15- to 20-minute meetings with each leader, according to two Japanese diplomats in South Africa.

Historically, a united Africa has been more of an imaginative leap than a realistic prospect. Africa is larger than the U.S., China, India, Japan and Europe combined. The 5,000 miles of territory stretching from Tangier in the north to Cape Town in the south are home to more than a billion people, speaking more than 2,000 languages.

ENLARGE

Artisanal gold miners walk to work in Kalana, Mali, in 2012. Africa-wide political unity has proven elusive, but economic integration may be easier.
Reuters

Perhaps unsurprisingly, the leading advocates for a united Africa have been romantics, visionaries or both. In his 1924 poem, "Hail! United States of Africa," Marcus Garvey saw unity as a way to liberate Africans from foreign repression. He tapped himself as "Provisional President of Africa," according to Colin Grant, the author of a biography of Garvey. That dream was still alive in 1979, when Bob Marley released "Africa Unite," singing, "How good and how pleasant it would be before God and man/ To see the unification of all Africans."

As colonialism came to an end after World War II, many of Africa's new leaders argued that the continent's economic and social development required political unity. At a 1963 summit of African leaders, Kwame Nkrumah, the first president of newly independent Ghana, warned that if they "let this grand and historic opportunity slip by, then we shall give way to greater dissension and division among us, for which the people of Africa will never forgive us."

Perhaps the most vocal proponent of African unity was Libya's Col. Gadhafi. About 10 months before he was overthrown and slain in 2011, the dictator told an audience in Senegal that Africa should have a single navy to combat piracy. He also argued for a single African currency and lobbied for a united government (to be based in Libya).

Gadhafi won endorsements for a U.S. of Africa by supporting cash-strapped African leaders. He also picked up 15% of the African Union's overall membership dues, according to the Center for Strategic and International Studies, a Washington think tank. (The AU didn't respond to questions about Libya's financial contributions.)

At a 1991 meeting in Nigeria, African leaders did agree to unite the continent's smaller regional trading blocs. The treaty, adopted a few years later, set out a road map for creating free-trade zones, a continental customs union and ultimately a single currency for one massive market by 2028.

But Gadhafi had even bolder ambitions and pressured a group of African leaders, meeting in Libya in 2005, to set a deadline of 2015 for creating a government for a U.S. of Africa. Ugandan President Yoweri Museveni, who headed this effort at political federation, later shifted his stance, backing economic integration instead, according to his spokesman, Ofwono Opondo.

Foreign manufacturers have scant incentive to invest in Africa's bite-sized economies when their suppliers can't easily move goods across borders. East Africa's biggest economy, Kenya, is smaller than that of Madison, Wis., according to the Brookings Institution, a Washington think tank.

And because most African economies sell a lot of raw commodities and manufacture very little, they don't buy much from each other either. Intra-Africa trade amounts to just 12% of the continent's total trade, the AU says. In Europe, it is 60%; in North America, it is 40%.

Still, signs of integration are slowly surfacing and may help spur further growth. In West Africa, eight countries maintain a common currency plus a central bank; in Central Africa, six more do the same. East Africans can now travel within the region using only their national identity cards. East and southern African leaders aim to establish a customs-free trade zone this year.

The U.S.-Africa summit is likely to reinforce what some experts say has become central to Africa's future: Unity is no longer about ideology but economics.

"Establish the veins through which the economy's lifeblood will flow," says Jakkie Cilliers, executive director of the Institute for Security Studies, a Pretoria think tank. "No one leader can push African integration. Those days are gone—and they should be gone."

—Nicholas Bariyo in Kampala, Uganda, Heidi Vogt in Nairobi and Drew Hinshaw in Accra, Ghana, contributed to this article.

A central government for Africa would make things worse. Any government on the continent interested in the benefits of free trade and free migration should unilaterally 1) remove trade barriers and 2) open the nation's borders.

All they have to do is give individual property rights to each individual. The individual as the ultimate strength of a nation is what gives the United States its strength. Inalienable rights for subservience of government to the will of the voters, predicate the growth energies of a dynamic economy. This saves civil liberties from the political animals who prey upon utterances to silent criticism. Ask Putin, Reid, Pelosi, Clinton, and so many other Progressives. Africa can become a USA. All it has to do is ditch the village, embrace individual property rights concepts, and embrace free enterprise and the chaos of liberty. Soon afterward, Africa will become the new exceptionalism and the rest of the earth can beat a path to their door!

This is an absurd fantasy. Africa isn't even one entity geographically, because the Sahara is as much of a barrier keeping north Africa from sub-Saharan Africa as the Mediterranean keeps Europe from north Africa. Also, Muslim Africans and Christian Africans don't get along - at all. Nigeria will eventually split along religious lines like Sudan did (much to the benefit of southern, wealthier, better educated, more U.S. oriented and Christian Nigerians). Africa is racked by tribalism, diffusely settled, with very poor infrastructure. There is no reason for it to be one nation. I sincerely hope some nations (like South Nigeria) are able to conquer their corruption and crime and become examples to the rest of the continent, and everyone can improve their lives, but an appeal to the authority of an insane rapist (Gaddafi), a black racist (Garvey), a man who thought a politician was god (Marley), and a politician who thinks himself a god (Obama) is hardly an argument. Absurd!

What a shame that a continent so bountiful in natural resources should be so divisive and noncooperative. There's just no reason for such poverty there. It's a disgrace. Of course that's true of a lot of other places as well.

The UN just released
a report saying the world will be at 10.1 billion by 2100 and 36% will be
Africans up from 14% now, who can’t by the way feed themselves and is only
enabled by 20th century Western technology. That’s up from 125
million or 8% of world population in 1900.

In 1900 Africa had
125 million population or 8% of world total while now it has almost 1 billion
and 15% of world total…most who can’t even feed themselves without Western
technology, assistance and aid.

TRILLIONS, not just
BILLIONS have been given to them and what does it do? ALL they have
accomplished with that money is endless civil wars and more poverty AND LOTS MORE PEOPLE needing even more assistance.

The LAST thing Africa needs is Super Centralization! Africa is by far the MOST ethnically, genetically, politically and culturally diverse region of earth! Big Countries like Nigeria, Sudan and Congo are falling apart under the crushing pressures of ethnic and religious warfare. A Super State invites Super Tyranny to make it work! Africa desperately needs Decentralization and loosening of the noose of too much Government and too little ability to enforce even basic law and order. The EU has produced stagnation in less diverse and violent Europe. Does Africa ALWAYS have to follow the Worst Practices of politics and economics?

lol, there isn't even a united states of ethiopia or sudan. there is barely a united state of mali. meanwhile, thousands are killed, raped and tortured in nigeria, the democratic republic of congo and the CAR.

speaking of democracy and republics or lack thereof, let's start with regular, fair and peaceful national and local elections before attempting "unity". (i'm looking at you, mr. mugabe.) free intra-african trade and elimination of border checks would be a welcomed second step.

Colonel Gadhafi tried to unify Libya with Syria as well, forming a United Arab Republic. Apparently, if two noncontiguous countries with borders drawn by Europeans fail, the best choice is to unite them and engage in terrorism.

How has that worked out for the people of those lands?

In Africa, ethic differences and immense geography seriously complicate unification. What Africans might do is less glamorous but has more potential: cooperate where shared goals and shared resources can benefit all sides. Electrical power and reduced tariffs might be good places to start. As the article points out, corruption and a true war on women are both obstacles to development.

@ALY-KHAN SATCHU If you do not adopt universal inalienable property rights concepts, you will further devolve until the African disappears or becomes a museum peace. If you do, you stand to be the free enterprise exceptionalism continent of potent force and purpose. The choice is yours and so far those choices have been what I would call, wrong! Put your feet on mars or in the memory books!

@Lee Zehrer First of all, the UN says there are not an unusual number of orphans in Mexico City. There are 2,000,000+ adolescent orphans roaming Mexico city. That's correct, two million orphans in one city alone. This means you do not trust UN figures and that the Mexican government must be supporting the transportation of children from central America to the US.

The real difference between the United States and every other country in the world is that here we have and practice individual property rights. We have property in self and from this comes all our other rights, the end of slavery, women's, suffrage, property ownership, freedoms of thought and religion. All Africa has to do is ditch the socialist dolt village and embrace Constitutional Personal Property Rights as an Inalienable condition of human life. That said, their current servitude to the rest of the world will end, and Africa will become a robust master on our planet. That is the real difference!

@John Shniper All these things are true if you do not have the basic tenants of human rights: limited constitutional government, embracing property rights in self as written in a bill of rights, and a recognition that limited liberties are all that individual citizens should give to any government. The EU suffers from this same absence of property rights concepts. As a result, 100,000,000 European bureaucrats spend other people's money until it is gone. And what freedoms or prosperity does the European have to show for it? Nothing but a growing anger as the EU citizen realizes they have been taken for a ride which begins and ends in war and destruction. Africa should become smarter than that.

It is the messy dysfunction of individual freedoms and free enterprise that cured most diseases, made American poor wealthy by African standards, fed the world, defeated communism, put your footprints on the moon, and defeated communism. It is the power of the individual as expressed in the chaos of freedom which insures the survival of citizen voters and compels the destruction of tyranny. Do not believe yet: Watch the American example in the next 2+ years, and learn.

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